Polymer waveguide WDM channel selector operating over the entire C and L bands.

A tunable channel selector operating over both the C and L bands of wavelengthdivision-multiplexing optical network is proposed based on a thermo-optic tunable Bragg grating device in a polymer waveguide. A tilted Bragg grating cascaded with an asymmetric Y-branch waveguide effectively implements a small Bragg-reflection wavelength filter that does not require an external circulator. To increase the operating wavelength span of the channel selector, two Bragg gratings with different periods are fabricated on a single substrate for covering C and L bands, respectively. A wide tuning range over 80 nm along with a narrow bandwidth is demonstrated. Moreover, the polarization dependence of the reflection spectrtun is observed to be less than 0.1 nm. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement